1. Field of the Invention
The present invention generally relates to a medical image processing apparatus and method, and more particularly to a medical image processing apparatus and method for detecting a pleural plaque (pleural thickening plaque). The invention also relates to a computer readable recording medium on which is recorded a program for causing a computer to realize a function corresponding to the invention.
2. Description of the Related Art
Recently, there has been a demand, in the medical field, for measures to detect a pleural plaque (pleural thickening plaque) that causes calcified thickening of parietal pleura by image diagnosis.
In order to find a pleural plaque, as is common to a general diagnosis of a lesion site, a radiological reader interprets a medical image of a subject to find a lesion site or observes the state of the lesion site to find an abnormal tumor pattern. There have been possibilities that such abnormal patterns are overlooked due to the difference in image interpretation ability among radiological readers who observe/interpret radiation images or misapprehended due to subjective judgment of the radiological readers.
Consequently, in the image diagnosis of pleural plaques, a computer-assisted technology for accurately detecting such pleural plaques is demanded.
For example, a method of generating a medical image in which, in order to confirm an abnormal pattern candidate area in a lung field, a nodular area which is an abnormal pattern candidate area is identified, and a malignant region is depicted by extracting an irregular portion, a low luminance portion, and a high luminance portion of the nodular area is disclosed as described, for example, in Japanese Unexamined Patent Publication No. 2009-089847.
Further, a method in which a CT imaging is performed by administering a contrast agent and an abnormal region (embolus) in a lung field is automatically detected is also disclosed as described, for example, in U.S. Pat. No. 7,583,829.
The method disclosed in Japanese Unexamined Patent Publication No. 2009-089847, however, can not directly detect an abnormal pattern itself because an abnormal pattern is found by radiological reading first and then an abnormal region is confirmed.
The method disclosed in U.S. Pat. No. 7,583,829 has a problem that an abnormal pattern can be detected by image diagnosis only in a limited area adjacent to a contrast enhanced blood vessel and an abnormal pattern present in an area not contrast enhanced can not be detected. Further, the method requires CT imaging by administering a contrast agent, causing a problem of a burden on a patient.
In view of the circumstances described above, it is an object of the present invention to provide a medical image processing apparatus and method capable of accurately detecting a pleural plaque candidate by detecting a pleural plaque candidate through the expansion of diagnosable image area and a reduced burden of contrast agent administration on a patient. It is a further object of the present invention to provide a computer readable recording medium on which is recorded a program for causing a computer to realize a function corresponding to the invention.